Monoazo dyestuffs and metal complex compounds thereof



United States Patent 2,813,853 Patented Nov. 19, 1957 MONOAZO DYESTUFFS AND METAL COMPLEX COMPOUNDS THEREOF No Drawing. Application June 27, 1955, Serial No. 518,398

Claims priority, application Switzerland June 29, 1954 6 Claims. (Cl. 260-145) The present invention relates to monoazo dyestulls and metal complex compounds thereof.

More particularly, the invention has especial relation to monoazo dyestuflls which, in the metal-free state, correspond to the formula wherein 2: represents a simple carbon-to-carbon bond or an -OCH2 bridge, and R stands for a radical of the benzene series having an hydroxyl or methoxy group in ortho-position to the azo group.

These dyestulls can be prepared by coupling 1 mol of the diazo compound of a Z-amino-l-hydroxyor -meth0xybenzene with 1 mol of a l-hydroxyacylamino- 7-hydroxynaphthalene corresponding to the formula wherein x has the previously-recited significance.

Illustrative of diazo compounds which may be used in building up the dyestuffs of the present invention are inter alia 2-amino-l-hydroxybenzene, 2-amino-1hydroxyhalogenobenzenes, Z-amino-1-hydroxy-nitrobenzenes, 2- amino-l-hydroxy-halogeno-nitrobenzenes, Z-amino-l-hydroxyacylamino halogenobenzenes, Z-amino-l-hydroxyacylamiz-tonitrobenzenes, the many Z-amino-l-hydroxybenzene-sulfonamides and their derivatives which are substituted at the nitrogen atom of the sulfonamide group by alkyl, halogenalkyl, hydroxyalkyl, alkoxyalkyl, aralkyl, carbocyclic and heterocyclic groups, Z-amino-l-hydroxysulfonyl'oenzenes and the corresponding Z-amino-lmethoxy compounds, etc. Worthy of special mention in this connection are Z-amino-l-hydroxybenzene-4-sulfonamide, 2-amino 1 hydroxybenzene-4-sulfonic acid methylamide, Z-amino-l-hydroxybenzene-4-sulfonic acid- (2-hydroxy) ethylarnide, Z-amino-l-hydroxybenzene-4- sulfonic acid-(3-methoxy)-propylamide, 2-amino-lhydroxybenzene-4-sulfonic acid benzylamide, Z-amino-l-hydroxybenzene-4-sulfonic acid cyclohcxylamide, Z-aminol-hydroxybenzene 4 sulfonic acid phenylamide-which may be further substituted at the phenylamido radical by a nuclearly bound carboxyl, acylamino, sulfonamido, sulfonic acid methylamido or sulfonic acid dimethylamido groupand Z-amino-1-hydroxy-4-methylsulfcnylbenzene.

The most important of the aforementioned l-hydroxyacylamino-7-hydroxynaphthalenes are l-hydroxyacetylamino-7-hydroxynaphthalene and l-carbo-(2-hydroxy)- ethoxyamino-7-hydroxynaphthalene. These are conveniently prepared from the corresponding chlorocylamino com ounds by heating to elevated temperature in formamide.

The coupling of the diazotized 2amino-l-hydroxyor 5 -methoxy-benzenes with the aforcdefined l-hydroxy acyla:nino-7-hydroxynaphthalencs is advantageously carried out in alkaline medium; the products are worked up on; isolated in per se conventional manner.

With the metal-free monoazo dyestuffs, wool can be 19 dyed by an after-metallizing or single bath metallizing process in shades which are fast to washing, fulling and light. In this manner, blue-gray, gray to olive shades are obtained with chromium-yielding agents, and blue to gray shades with cobalt-yielding agents.

15 The conversion of the metal-free monoazo dyes into the metal complex compounds is preferably effected with chromium and cobalt-yielding agents. Agents of this character comprise for example chromium salts such as chromic fluoride, chromic sulfate, chromic formate, potassium or ammonium chromic sulfate, sodium or potassium chromate, and sodium or potassium bichromate, and cobalt salts such as cobaltous acetate, cobaltous formate and cobaltous sulfate. The metallization is advantageously carried out in an aqueous slurry or solution or in an organic medium, for example in formamide or in a melt of an alkali metal salt of a low molecular aliphatic monocarboxylic acid. In the latter case, use can also be made of insoluble heavy metal compounds, as for example cobalt hydroxide and cobalt carbonate. Especially advantageous is mctallization in aqueous caustic alkaline medium, the metal salts being added in the presence of compounds, such as tartaric acid, citric acid, lactic acid and the like, which keep chromium and cobalt in complex combination in solution in caustic alkaline medium. If the monoazo dyestuffs contain an ortho-hydroxy-ortho'-methoxy-azo grouping as the grouping to be metallized, then the metallization is carried out with splitting of the methoxy group. This is effected by heating the dyestuif to elevated temperature in organlc medium, for example in a glycol (e. g. ethylglycol, butylglycol, ethylpolyglycol). The metallization of the monoazo compounds is in all cases carried out in such manner that there is less than one atom of metal per molecule of monoazo compound. In this way, there are prot used for example the so-called l:2complexes which contain approximately one atom of metal for each two rztolecules of monoazo compound.

The obtained metal-containing azo dyestuffs are precipitated from aqueous medium by the addition of sodiuzn chloride, if necessary after pouring the organic metnllization solution into Water, thereupon filtering, if desired, washing, and then drying. These possess an outstanding neutral drawing capacity for wool; they dye the latter from a neutral dyebath and silk and tussah from a weakly acid dyebath in blue-gray, gray to olive shades of very good fastness to washing, fulling and light; they are also suitable for dyeing leather and, more especially, for dyeing synthetic nitrogen-containing fibers, such as polyamide fibers (e. g. nylon, Perlon, etc.). Their good solubility in polar solvents, such for example as acetone, dimethyl-forntamide and tetrahydrofurane, makes it possible to employ the new dyestuffs for dyeing artificial fibers spun from organic solutions (such for example as acetate silk, Dacron and the like).

In many cases, mixed metal complex compounds-01)- tained by metallizing mixtures of two or more monazo dyestulls of the present inventionare superior in dyeing properties to the individual metal complex compounds. Such mixed metal complex compounds constitute a. further phase of the present invention.

The following examples illustrate the invention Without, however, being limitative thereof. In such examples, the parts and percentages are by weight, and the temperatures are in degree centigrade.

EXAMPLE 1 20.2 parts of 2-amino-1-hydroxybenzene-4-sulfonic acid methylamide are diazotized by means of a solution of 6.9 parts of sodium nitrite and 30 parts of water in a mixture of 20 parts of 30% hydrochloric acid and 100 parts of water at 5 The diazo suspension is combined at 0-5" with a solution of 22 parts of l-hydroxyacetylamino-7- hydroxynaphthalene, 6 parts of sodium hydroxide, 20 parts of anhydrous sodium carbonate, 350 parts of water and 10 parts of a pyridine base mixture. The entire reaction mixture is vigorously stirred for several hours at 05. At the end of this time, the coupling reaction is finished and the almost completely precipitated monoazo dyestufi is isolated. It corresponds to the formula EN 0 to dHPoH EXAMPLE 2 21.6 parts of 2-amino-l-hydroxybenzene-4-sulfonic acid ethylamide are coupled, after the manner described in the preceding example, with 25 parts of 1-carbo-(2'-hydroxy) ethoxyamino-7-hydroxynaphthalene. There is thus obtained a monoazo dyestufi which corresponds to the formula OH OH HN so he 1' 3) NH CsHr-OH and which is very similar to the product of Example 1.

1 carbo (2-hydroxy)-ethoxyamino-7-hydroxynaphthalene is obtained by heating l-carbo-(2'-chloro)-ethoxyamino-7-hydroxynaphthalene to 160 in formamide for several hours.

EXAMPLE 3 43 parts of the monoazo dystufi obtainable according to Example 1 are dissolved in 1500 parts of water. 16 parts of sodium bichromate are added to the solution which is then boiled under reflux until complex formation is complete which requires several hours. The precipitated, filtered and dried chromium-containing azo dyestufi, which corresponds to the formula is a dark powder which dissolves in water to yield a blue coloration and in concentrated sulfuric acid to yield a red coloration. It dyes wool, silk and synthetic polyamide fibers in blue-gray shades of excellent fastness to washing, fulling and light.

EXAMPLE 4 21.5 parts of the monoazo dystuif obtainable according to Example 1 and 23.7 parts of the monoazo dyestzrff obtainable according to Example 2, are dissolved in 1000 parts of water at 90 with the aid of 6 parts of sodium hydroxide. A solution of 24 parts of sodium bichromate and 4 parts of sodium hydroxide in 100 parts of water are then added to the dyestufl solution, followed by parts of a 20% aqueous glucose solution. The temperature of the metallization solution is then maintained at 95 until complex formation is complete, after which the chromium-containing azo dyestufi is isolated and dried. The product which is a mixture of dyestuffs of the formulae 0 Cr-O a f r-OH NH and dyes wool, silk and synthetic polyamide fibers in bluegray shades of excellent fastness to washing, fulling and light.

dyestuff is precipitated, filtered OE and dried. It is a mixture of dyestuffs of the formulae -0 f EXAMPLE 5 N'=N 44.4 parts of the monoazo dystufi obtained according HN to data of Example 1 by coupling 21.6 parts of 2-amino- 1 l-methoxybenzene-4-sulfonic acid methylamide with 22 so, 4 parts of l-hydroxyacetylamino-7-hydroxynaphthalene, are 10 i HP'OH dissolved in 400 parts of ethylglycol. 50 parts of potasslum chromium sulfate are added to the solution which is then heated to 140' until the complex formation is com- 0 ,9, plete. The metallization mass is poured into 1200 parts of 2 water, and the chomium-containing azo dyestuff is salted out, filtered off and dried. It is identical with the product obtained according to Example 3. 2:

0 so EXAMPLE6 (mull-0H NH 43 parts of the monoazo dystufl obtainable according dam, to Example 1, are dissolved in 800 parts of warm water. and To the resultant solution there is then added a mixture (31H: of 28.2 parts of cobaltous sulfate, 7.6 parts of tartaric g acid, 35 parts of sodium hydroxide solution and 350 HO-HlCzO 1 parts of water. Complex formation takes place instantaneously. The copper-containing azo dystulf which corresponds to the formula NH 30 O /%D0 0 :l I H N1. 0 EN I do -1r=N 41H OH r m HN la. 4 0 0 (hm-0H NH is precipitated, filtered ofr' and dried. It dyes wool, silk and synthetlc polyamlde fibers in reddish gray shades of 45 and dyes WOO], Silk and synthetic polyamide fib in very good fastness properties.

EXAMPLE 7 21.5 parts of the monoazo dystuff obtained according to Example 1, and 23.7 parts of the monoazo dyestufl' obtained according to Example 2 are dissolved at approximately 90 in 1000 parts of water with the aid of 30 parts of 30% aqueous sodium hydroxide solution. parts of hot aqueous 20% cobaltous sulfate solution are added to the dyestuff solution. Upon completion of the ensuing complex formation, the cobalt-containing azo blue-gray shades of excellent fastness to washing, fulling and light.

The following Table 1 exemplifies additional metalcontaining azo dyestuffs which can be prepared according to the preceding examples. In such table the dyestuffs are characterized in column (A) by the Z-amino-lhydroxyor -methoxy-benzene employed in preparing the diazo compound, in column. (B) by the l-hydroxyacylamiuo-7-hydroxynaphthalene, and in columns (C) and (D) by the shades of the dyeings on Wool obtained with the chromium-containing or cobalt-containing azo dyestuffs.

Table I 2-amlno-1-hydroxy-4- l-hydrnxyacetylamino- Blue-gray violet-gray.

7-hydrcxynaphtlmlenc.

do u.

c do

blue-gray.

reddish-gray.

Table 2 exemplifies mixed metal complex compounds 7 2. The mono'azo dyestuflf which corresponds to the from two monoazo dyestuffs which can be obtained after formula the manner set forth in Example 1. These mixed metal complex compounds are characterized by the content of metal-free monoazo dyestuii which is reacted with one atom of metal; they contain for each atom of metal about =1: 2 mols of the mixture of the two monoazo compounds. In the table, column (E) sets forth the metal used for EN metallizing the mixture and column (F) indicates the shade of the dyeing obtained on Wool with the metalcontaining azo dyestufl. 31-03 Table 2 4 First Metal-Free Second Metal- 3. The monoazo dyestufi which corresponds to the Monoazo Dye- Free Monoazo formula stnfi Dyestufi Example N0.

According According O--Or0 M01 to M01 to IT Example Example I I=N 1 1 1 8 Cr blue-gray.

1 1 1 10 Cr Do. EN 1 1 1 11 Cr Do. 6 1.5 1 0. 81 go, o 0

1 2 r o. l 1 2 1 22 Or Do. I 1- 1 10 1 11 Or Do. NH 1.5 11 0.5 15 Or Do. I 1.5 11 0.5 16 Or Do. H1

1 2 1 22 (J0 reddish-gray. l 1: l s s s o o. 1 m 1 22 C0 D0. 4. A mlxture of monoazo dyestuffs of the formulae o '7 EXAMPLE 53 I N A dyebath is prepared from 4000 parts of water, one part of the chromable dyestuff obtained according to EN Example 1, 1 part of potassium chromate, 7 parts of ammonium sulfate and 10 parts of Glauber's salt, and 100 parts of wool are entered into the bath at 40. The bath 1 1- is heated to boiling in the course of 30 minutes and then is maintained at the boil for 90 minutes. The dyed wool 40 13B! is then withdrawn from the bath, washed with water and stuff obtainable according to Example 3, 4000 parts of water and 5 parts of ammonium sulfate. The bath is (QCIHPOH heated to boiling in the course of 30 minutes and is main- NH tained at the boil for 60 minutes. After cooling for a (3211' short time, the dyed wool is withdrawn from the bath, rinsed with water and dried.

Synthetic polyamide fibers are dyed in like manner, as is also silk for which a somewhat lower temperature (for example 95 is employed. 0,31

Having thus disclosed the invention, what is claimed is:

1. A member selected from the group consisting of H0-H C 0 A monoazo dyestuffs and the corresponding cobalt-contain- 0 ing and chromium-containing monoazo dyestuffs, said I Q B dried. O

EXAMPLE s4 N=N 100 parts of wool are entered at 40 into a dyebath 45 consisting of 1 part of the chromium-containing azo dyei and monoazo dyestuffs, in the metal-free state correspond- NH ing to the formula RN=N NH-C-z-lower alkylene-OH I wherein 1: represents a member selected from the group EN consisting of a simple carbon-to-carbon bond and a a -OCHz-bridge, and R stands for a radical of the benzene series having in ortho-position to the azo group a member P selected from the group consisting of hydroxyl and NH methoxy groups. (ER:

11' 12 S. The monoazo dyestufl which corresponds to the 6. The monoazo dyestuif which corresponds to the formula formula 0 Or-O 0 00-0 If 1 2- N=N 5 EN EN 410 A0 {an on 1 ('21: on $11. 10 NH fiIe-OCH:

References Cited in the file of this patent 15 UNITED STATES PATENTS 2,543,610 Steinemann Feb. 27, 1951 2,602,080 Grimmel et a1. July 1. 1952 2,623,871 Schetty et a1 Dec. 30, 1952 

1. A MEMBER SELECTED FROM THE GROUP CONSISTING OF MONOAZO DYESTUFFS AND THE CORRESPONDING COBALT-CONTAINING AND CHROMIUM-CONTAING MONOAZO DYESTUFFS, SAID MONOAZO DYESTUFFS, IN THE METAL-FREE STATE CORRESPONDING TO THE FORMULA WHEREIN X REPRESENTS A MEMBER SELECTED FROM THE GROUP CONSISTING OF A SIMPLE CARBON-TO-CARBON BOND AND A -OCH2-BRIDGE, AND R STANDS FOR A RADICAL OF THE BENZENE SERIES HAVING IN ORTHO-POSITION TO THE AZO GROUP A MEMBER SELECTED FROM THE GROUP CONSITING OF HYDROXYL AND METHOXY GROUPS. 